• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2007년도 SMT/PCB 기술세미나
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• pp.37-47
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• 2007

Factor : Structure Metal pad & SMO size Board level TC test : - Large SMO size better Board level Drop test : - Large SMO size better Factor : Structure Substrate thickness Board level TC test : - Thick substrate better Board level Drop test : - Substrate thickness is not a significant factor for drop test Factor : Material Solder alloy Board level TC test : - Not so big differences over Pb-free solder and NiAu, OSP finish Board level Drop test : - Ni/Au+SAC105, CuOSP+LF35 are better Factor : Material Pad finish Board level TC test : - NiAu/NiAu is best Board livel Drop test : - CuOSP is best Factor : Material Underfill Board level TC test - Several underfills (reworkable) are passed TCG x500 cycles Board level Drop test : - Underfill lots have better performance than non-underfill lots Factor : Process Multiple reflow Board level TC test : - Multiple reflow is not a significant actor for TC test Board level Drop test : N/A Factor : Process Peak temp Board level TC test : - Higher peak temperature is worse than STD Board level Drop test : N/A Factor : Process Stack method Board level TC test : - No big difference between pre-stack and SMT stack Board level Drop test : - Flux dipping is better than paste dipping but failure rate is more faster

• Current Photovoltaic Research
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• 제4권4호
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• pp.140-144
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• 2016

In this paper, core-shell structure of nickel/gold (Ni/Au) conductive layer on poly-methyl-methacrylate (PMMA) micro-ball was fabricated and its conduction property was investigated. Firstly, PMMA micro-ball was synthesized by using dispersion polymerization method. Size of the ball was $2.8{\mu}m$ within ${\pm}7%$ deviation, and appropriate elastic deformation of the PMMA micro-ball ranging from 31 to 39% was achieved under 3 kg pressure. Also, 200 nm thick Ni/Au conductive layer was fabricated on the PMMA micro-ball by uniformly depositing with electroless-plating. Adhesion of the conductive layer was optimized with help of surface pre-treatment, and the layer adhered without peeling-off despite of thermal expansion by collision with accelerated electrons. Composite paste containing core-shell structured particles well cured at low temperature of $130^{\circ}C$ while pressing the test chip onto the substrate to make electrical contact, and electrical resistance of the conductive layer showed stable behavior of about $6.0{\Omega}$. Thus, it was known that core-shell structured particle of the Ni/Au conductive layer on PMMA micro-ball was feasible to flexible electronics.

• 마이크로전자및패키징학회지
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• 제14권1호
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• pp.1-9
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• 2007

OSP(Organic Solderability Preservatives)표면처리는 저비용, 고신뢰성, 친환경 특성으로 기존의 금속계 표면처리인 Ni/Au 표면처리를 대체할 수 있는 공정으로 관심 받고 있다. 그러나, OSP는 저분자로 구성된 유기물이므로 여러 온도공정으로 구성된 전자패키지공정에서 제품의 변색이 필연적으로 발생하여 전체 양산수율에 미치는 영향은 매우 크다. 본 연구에서 OSP 처리된 제품을 전자패키지 공정별로 발생하는 변색수준에 따라서 시편을 분류 및 채취하여 변색원인분석 및 솔더조인트 특성평가를 수행하였으며, 기존의 표면처리공정인 Ni/Au 처리된 제품과 통계 적으로 비교 분석하였다. 따라서 변색원인에 대한 분석을 통하여 OSP 처리된 전자패키지 제품에 적용 시 발생하는 공정문제점에 대한 해결책을 제시하였다.

• 대한치과기공학회지
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• 제31권4호
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• pp.15-23
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• 2009

The aim of this study was to evaluate the bond strength of using a Au bonding agent applied on cp-Ti and nonprecious metal-gold-ceramic system. Metallic frameworks(diameter: 5mm, height: 20mm)(N=56, n=7per group) cast in Ni-Cr alloy, Co-Cr alloy and cp-Ti were obtained using acrylic templates and airborne particle abraded with $110{\mu}m$ aluminum oxide. Au bonding agent was applied on wash opaque firing as intermediate layer. SEM and SEM/EDS line profile were performed on the cutting the cross-section of the metal substrate-porcelain with intermediate Au coating. Groups were tested using shear bond strength(SBS) testing at 0.5mm/min. The mean SBS values for the ceramic-Au layer-metal combination were significantly higher than those ceramic-metal combination. While ceramic-Au layer-cp-Ti combinations failed to increase bond strength instead of using a titanium bonding porcelain. The appication of using Au intermediate layer significantly improve the bond strength combination with metal-ceramic system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제16회 학술발표회 논문개요집
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• pp.55-55
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• 1999

• 한국지구과학회지
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• 제35권4호
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• pp.259-266
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• 2014

폐 PCBs의 스크랩으로부터 염소-차아염소산염 용액을 이용하여 Au와 Ag를 친환경적이고 효과적으로 용출시키고자 하였다. PCBs에 Cu, Sn, Sb, Al, Ni, Pb, Au 등과 같은 유용금속이 함유되어 있는 것을 EDS 분석으로 확인하였다. 최대 Au 용출율은 1%의 광액농도, 2:1의 염산:차아염소산나트륨 그리고 2 M의 NaCl 농도조건이다. Au 회수율이 가장 높은 메타중아황산나트륨 농도는 3 M에서였다. 염소-차아염소산염이 폐 컴퓨터에 함유되어 있는 Au와 Ag를 효과적으로 용출시킬 수 있는 용매제 임을 그리고 메타중아황산나트륨이 Au를 간단하게 침전시킬 수 있는 첨가제임을 확인하였다.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 추계 기술심포지움
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• pp.75-87
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• 2001

Three different kinds of substrate used in this study : bare Cu substrate, Ni-P/Cu substrate with a Ni-P layer thickness of $5\mu\textrm{m},$ and Au/Ni-P/Cu substrate with the Ni-P and Au layers of $0.15\mu\textrm{m}$ and $5\mu\textrm{m}$ thickness respectively. The wettability of various Sn-base solders was affected by the substrate metal finish used, i.e., nickel, gold and copper. On the Au/Ni-F/Cu substrate, Sn-base solders wet better than any of the other substrate metal finishes tested. The interfacial reaction between various substrate and Sn-base solder was investigated at $70^{\circ}C,$ $100^{\circ}C,$ $120^{\circ}C,$ $150^{\circ}C,$ $170^{\circ}C$ and $200^{\circ}C$ for reaction times ranging from 0 day to 60 day. Intermetallic phases was formed along a Sn-base solder/ various substrate interface during solid-state aging. The apparent activation energy for growth of Sn-Ag/Cu, Sn-Ag-Bi/Cu, and Sn-Bi/Cu couples were 65.4, 88.6, and 127.9 Kj/mol, respectively. After isothermal aging, the fracture surface shoved various characteristics depending on aging temperature and time, and the types of BGA pad.

• 대한화학회지
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• 제36권5호
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• pp.685-691
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• 1992

디포스핀을 포함한 몇가지 $d^8$ 전이금속착물$(MCl_2PP)$은 출발물질 $K_nMCl_m$을 사용하여 합성하였다. 중심금속(M)은 Ni(II), Pd(II), Pt(II), Au(III)이며, 디포스핀(PP)은 bis(diphenylphosphino)methane(dppm), bis(diphenylphosphino)ethane(dppe), bis(diphenylphosphino)propane (dppp) 및 bis(diphenylphosphino)ethylene(dppety)이었다. 착물의 조성이나 특성은 원소분석과 $^1H-NMR$, $^{31}P-NMR$ 및 UV-Visible 스펙트럼을 이용하여 확인하였다. 이들 착물의 촉매적 활성은 3(2H)-furanone 및 cyclic carbonate 생성반응에 대하여 각각 조사하였다. 2-methyl-3-butyn-2-ol로부터 생성물 3(2H)-furanone을 얻은 반응 (1)에서 Ni(II)-, Pd(II)-diphosphine 착물은 좋은 촉매적 효과를 나타내었다. 그러나 이들 diphosphine 착물들은 cyclic carbonate 생성반응 (2)에 대해 촉매제로서의 활성을 거의 나타내지 않았다.

• 마이크로전자및패키징학회지
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• 제25권4호
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• pp.155-161
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• 2018

강성도가 서로 다른 polydimethylsiloxane (PDMS) 탄성고분자와 flexible printed circuit board (FPCB)로 이루어진 PDMS/FPCB 구조의 강성도 국부변환 신축기판에 $100{\mu}m$ 직경의 Cu/Au 범프를 갖는 Si 칩을 anisotropic conductive adhesive (ACA)를 사용하여 플립칩 본딩 후, ACA내 전도성 입자에 따른 플립칩 접속저항을 비교하였다. Au 코팅된 폴리머 볼을 함유한 ACA를 사용하여 플립칩 본딩한 시편은 $43.2m{\Omega}$의 접속저항을 나타내었으며, SnBi 솔더입자를 함유한 ACA로 플립칩 본딩한 시편은 $36.2m{\Omega}$의 접속저항을 나타내었다. 반면에 Ni 입자를 함유한 ACA를 사용하여 플립칩 본딩한 시편에서는 전기적 open이 발생하였는데, 이는 ACA내 Ni 입자의 함유량이 부족하여 entrap된 Ni 입자가 하나도 없는 플립칩 접속부가 발생하였기 때문이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.403-403
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• 2010

The Pt-Ni alloy is an electro-catalyst of interest in the low temperature direct methanol fuel cells(DMFCs). It has been already reported that the Pt-Ni alloy catalysts may even have enhanced activity compared to pure platinum catalyst, depending on how the surfaces are prepared. The order-disorder transition in bimetallic alloy such as $\beta$-CuZn, Cu3Au, and CuAu have been investigated greatly by x-ray diffraction. After annealing the bimetallic alloy, the crystal structure changes as observed in the order-disorder transition of Cu3Au which changes from the face centered cubic to a simple cubic structure. Pt-Ni bimetallic alloy has been already reported to have the face centered cubic structure. However, in nano-scale Pt-Ni bimetallic alloy crystals the crystal structures changes to a simple cubic structure. In this experiment, we have studied the order-disorder transition in Pt-Ni bimetallic nanocrystals. Pt/Ni thin films were deposited on sapphire(0001) substrates by e-beam evaporator and then Pt-Ni alloy were formed by RTA at 500, 600, and $700^{\circ}C$ in a vacuum environment and Pt-Ni nano particles were formed by RTA at $1059^{\circ}C$ in a vacuum environment. We measured the structure of Pt-Ni bimetallic alloy films using synchrotron x-ray diffraction and SEM.